Engine apart, looking at P&C's - what are my options?
 

Well, I ripped into the engine of the '82SC I bought a couple weeks ago. Although I've rebuilt a few motorcycle engines, I've never done a 911 engine before. So, with Wayne's books by my side, I started tearing it down. Although the engine was filthy, it came apart pretty easily. I was pleasantly surprised when I found all head studs intact - none broken. Then I got to the pistons and cylinders - not so pleasant. P/C #5 was severly scored along its skirt. The others, had some scoring, but to a much lesser degree. I have a feeling that they all will have to be tossed, but I haven't taken any measurements yet.

What are my options? Do I really need to spend $3000+, or are there less expensive options. A quick scan on ebay turned up a set of QSC (not familiar with this manufacturer) P&C for $1250. Has anyone used these before? Do used sets ever come up where someone is bumping up to a larger bore?

Thanks.

Geoff

Number 5 P&C are shown below
http://forums.pelicanparts.com/uploa...1168134137.jpg

http://forums.pelicanparts.com/uploa...1168134176.jpg

Henry Schmidt at supertec racing sells the QSC jugs with pistons that he matches, call him about I did and I received a great education on the subject from Henry.

I involved in the same rebuild as you on my 80'. My pistons and jugs were shot, which is where my 30% cylinder leak was coming from. I found that the best option you have if you have Nikisil is to send them to be re-plated by EBS or US Chrome or LN Engineering. They install a new set of JE's at that time and you get them back pretty quick. EBS has 3.0L with warmed up compression for around $1700, and 3.0 >3.2 sets for around $2500.

Beyond that you have of course Mahle, which every wrech I have talked to says is still hands down the best option.

What kind of intake? What kind of cams? Do you have smog requirements?

If going stock cams/intake, used in-spec. Mahle is the cheapest, around $500-800.

If you are planning to use radical cams and carbs/MFI/ITB's (individual throttle bodies), then JE pistons ($900) + QSC/Mahle 3.2 (95mm)/bored Mahle 3.2 (98mm)/Perfect Bore/Nickies cylinders are the best bet. Radical cams + intake usually not compatible with smog requirements.

Mahle will last the longest, but won't allow you to make the most power.

PM me, I can set you up with various options ....

cheers
Scott

Scott,

I'm going stock, no performance upgrades.

I emailed you. Thanks for your response.

Geoff

Geoff,
I have a new set of Mahles for sale; I PMd you.
regards,
Phil

If you have time, you call around to used parts sources, tons in the back of a copy of "Excellence" magazine. Also keep your eyes open on Pelican classifieds. I am in a similar situation and found a set from a fellow Pelican for 500 bucks.

I am no expert, this is my first Porsche engine as well, but a good set of used cylinders and pistons with new rings and the cylinders touched up with a grape hone should work. I don't think it is a 100% that the new rings will seat, but much better than 3000 bucks. Just make sure the used set has been measured to be withing specs.

Keep in mind that for the factory piston and cylinders there are:
- 4 different diameters ("tolerance groups")
- 4 different piston weight groups
- 2 different cylinder heights ("height groups")
And that's just for the Mahle, Koblesmidt (sp?) also supplied P&C's.

This makes replacing a single piston or P&C problematic. For that reason I'd go with a matched set of 6 P&Cs be it used or new.

-Chris